Which part of cluster state will be written to disk?

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1

cluster state contains many parts:
version
routingtable
nodes
metadata
blocks
customs
clusterName
routingNodes
settingsFilter
status
I only find that metadata in dsik. so my question is: are other parts be written to disk or not? if yes, where to find them? if no, why?

2

anyone can help?
I read source code(ES1.7) and met this problem which bothers me a lot.
in my mind, all state part should be written to disk. but turns ont not so based on what I found in code.

3

can I get answer for serious question like this in the forum?